I am answering from my iPod so forgive me if the spelling is naff.
You can get rid of photo gallery by uninstalling it.
The other thing is at some time you would have been asked what you wanted to with the photos when you plugged your camera in,you should at that point made sure that they went to your pictures folder.
To copy your pictures, just right click, then copy and then paste to your external drive.
If no one else posts I will try and answer any questions tomorrow.